ELECTRO-HYDRAULIC CONTROL APPARATUS AND METHOD FOR CONSTRUCTION MACHINERY

摘要

An electro-hydraulic control apparatus of a construction machinery comprises: a control valve installed in a hydraulic line between a hydraulic pump and an actuator and controlling operation of the actuator in accordance with displacement amounts of a spool disposed therein; a spool displacement adjustment valve outputting secondary pressure proportional to an input pressure command signal to the spool of the control valve to control the displacement amounts of the spool of the control valve; a pressure sensor detecting the secondary pressure output from the spool displacement adjustment valve; and a control unit outputting the pressure command signal to the spool displacement adjustment valve in accordance with a control signal of the construction machinery and correcting the pressure command signal when a pressure difference between the detected secondary pressure and designed pressure predetermined by the pressure command signal is beyond a preset allowable range.